The present invention discloses a dual-vortical-flow hybrid rocket engine, including a main body and a nozzle communicating with an end of the main body. The main body includes a plurality of disk-like combustion chambers arranged longitudinally, and a central combustion chamber formed along the axial portion and communicating the disk-like combustion chambers. Each of the disk-like combustion chambers is provided with a plurality of oxidizer injection nozzles at its inner circumference surface. Inside the disk-like combustion chambers, the oxidizer is injected in nearly the tangent directions of the circumference, and the injection directions are opposite for the neighboring disk-like combustion chambers, which creates vortical flows with opposite rotating directions so as to increase the total residence time of the combustion reactions of the oxidizer and the solid-state fuel in the disk-like combustion chambers of the present invention.